8/7/2019 IB-LabReport-Guidelines

1/3

IB Chemistry How to write a lab report

General

The IB program requires that 24% of our class time we spend doing some things related

to practical work. The laboratory work will consist of a variety of activities, most will

require the entire double period; some will take a few days to complete. For someexperiments complete instructions will be given; for others you will have to plan part or

all of the experiment yourself. Usually, you will be working in a group of 2-3 people, but,

occasionally you will be on your own. For most experiments you will write completereports. Some reports may involve only collection and analysis of data and writing of a

brief conclusion. You will always be told what is expected of you for each experiment.

Laboratory Notebooks

Your lab book is where the raw data is recorded at the time of the experiment. Your

report will then be written up using Microsoft Word and submitted on the due date.

Reports of laboratory workWhen you are writing in your lab report try to keep the thought in mind: could someone

else understand what I am doing, observing, calculating, writing etc. A scientists reportis the way that scientific discovery is communicated to the rest of the world.

The following is an outline of the various elements of a complete report. For each

specific report you will need to include some or all of these.

1. Experiment #, the date, and title of the experiment (this is required for everyexperiment).

2. Aim: a short (one to two sentences) statement of the purpose of the experiment,preferably written in your own words. (this is required for every experiment)

3. Introduction: this section should always begin with a clearly stated ResearchQuestion. The Research Question should not just be a repeat of the general problemprovided by the teacher. Rather, the Research Question should indicate what specific

aspect of the general problem you will be investigating.

Example

Poor research question: What factors affect rates of reaction?

Better research question: Are heterogeneous catalysts as effective as homogeneous

catalysts in the decomposition of 6 % hydrogen peroxide?

The next step is to provide the Background to the problem you are trying to solve.Specifically, this is the theory one should know to understand the experiment. The

Background will also lead to, or justify a prediction of what you think will happen in the

experiment, and it is called the hypothesis: a testable statement about what you think isgoing to happen when you measure one variable and you change another.

This leads to the last part of an Introduction. You need to specifically mention the

variables that you will hold fixed and the variables that you will change and measure(both independent and dependent i.e the same ones from your hypothesis).

4. Procedure: this section provides an outline of how you intend to carry out theexperiment. It may take some practice before you will be comfortable as to what details

8/7/2019 IB-LabReport-Guidelines

2/3

to include. The most important details are things like mass, volume, and concentrations of

chemicals and solutions, the type of glassware and equipment used, and any safety

precautions. These details not only provide relevant experimental information but alsoshow how you are keeping certain variables fixed, while changing others. Where

appropriate, it is important to outline why one approach is taken versus another. Keep in

mind to mention clearly what specific data will be recorded and how often themeasurements will be replicated. Write the procedure so that you, or someone else with

some science background, could perform the experiment.

The IB calls the sections 3 an 4 of the report Design.

5. Data and Observations: record all relevant data and observations. Report any changes

in procedure or unusual conditions. All numerical data, tables, and graphs should be

clearly identified and labeled. You should record all observed data not just calculatedresults. Correct units and significant figures must be used for all data. In addition, you

should indicate the level of uncertainty for each measurement. Also note that

experimental observations or details are both qualitative and quantitative.

6. Results and Calculations: results are different than data. Results are what happens to

the data after you do a calculation or plot a graph. They are what results after youmanipulate the data. Your presentation of the results might be in the form of a table, a

graph, or maybe a chart. How you present the results will depend on the experiment

these are part of the skills that you are required to learn. All tables, graphs etc should be

clearly identified and labeled. Furthermore it is necessary to show how you manipulatedthe data i.e what sort of calculations did you do. It is also important to calculate and

present the percent uncertainty for each of the measurements made. A brief explanation

of what you are doing at each stage of the calculation is just as important as the

calculation itself. Finally, where several similar calculations are needed, show one

example and give the results of the others.

The IB call the section 5 and 6 of the report Data Collection and Processing .

7. Conclusion and Discussion: This is the section where you draw conclusions about the

experiment as it relates to your aim and hypothesis. Any calculated results should becompared to values from the literature (i.e. accepted values from professional

laboratories) where possible. This section should include a discussion of errors, as well as

a consideration of the limitations of the experiment and suggestions for improvement.

In summary this section should include:

Conclusion about your aim or hypothesis

Evaluation of errors and limitations to the experiment Suggestions for improvements

The IB calls this section of the report Conclusion and Evaluation.

8/7/2019 IB-LabReport-Guidelines

3/3

Grading

Grades for the written reports will be given according to the five criteria listed in the IB

Chemistry score form. Each of the criteria is worth a maximum of six points. Manyreports will be graded on several but not all of the criteria. Some reports will be graded

on all criteria.

At the end of the course, your two top scores for each of five criteria will be used todetermine your IB internal assessment lab grade. The five criteria include the three

criteria that have been graded in your reports as well as two additional criteria. These

criteria (Manipulative, and Personal skills) are based on your overall performance in thelab and how well you worked with others. Since the first three criteria are worth six

points each and each one is assessed twice and the last two criteria are worth six points

each and each one is assessed once, your final IB internal assessment lab grade will be

based on 48 points. This in turn is 24 % of your total IB grade.

Original Source: Dr.Cs website.